| 162 | ÷ | x | × | ( | 50 | − | x | ) | = | 72 | ÷ | ( | 50 | − | x | ) | × | x |
| 方程两边同时乘以: | x | , | ( | 50 | − | x | ) |
| 162 | ( | 50 | − | x | ) | ( | 50 | − | x | ) | = | 72 | x | x |
| 162 | × | 50 | ( | 50 | − | x | ) | − | 162 | x | ( | 50 | − | x | ) | = | 72 | x | x |
| 8100 | ( | 50 | − | x | ) | − | 162 | x | ( | 50 | − | x | ) | = | 72 | x | x |
| 8100 | × | 50 | − | 8100 | x | − | 162 | x | ( | 50 | − | x | ) | = | 72 | x | x |
| 405000 | − | 8100 | x | − | 162 | x | ( | 50 | − | x | ) | = | 72 | x | x |
| 405000 | − | 8100 | x | − | 162 | x | × | 50 | + | 162 | x | x | = | 72 | x | x |
| 405000 | − | 8100 | x | − | 8100 | x | + | 162 | x | x | = | 72 | x | x |
| 405000 | − | 16200 | x | + | 162 | x | x | = | 72 | x | x |